There's been something before about multiple actions being passed, IIRC it was thought that modifying the existing functions to accept an array would add a overhead which wasnt really needed when you could mearly have a new function for it.

Well, I suppose it really depends, if the overhead doesn't make sense to that function.

I forget what other function it was that wanted to be added to the add_filter and add_action, but it didn't make sense at the time.

Add overhead the majority of people are not going to use will lower the limit of actions and filters that can be run before the total equals more than a second in itself.

Adding an if statement might not seem like much, but the CPU still has to make an decision on whether or not it should choose the branch that goes into the if statement or the one that ignores it. If it chooses wrong, then it has to start over.

However, making multiple function calls might be more than the overhead of the single if statement.

A little late for this. Will consider it early in 2.9 cycle. Shane, your 8650.2.diff patch won't work... you're not calling the new function properly. You're still passing $filter when you've removed the foreach loop.

each function can have its own priority and number of arguments, and this renders the whole idea more or less pointless. and that is not to mention the clunky looking syntax with classes (especially when they're mixed up):